Background: A detailed evaluation of hemodynamics, supportive morphology, and deformation may help uncover the pathophysiology of hypertrophic obstructive cardiomyopathy (HOCM) and the changes wrought by alcohol septal ablation (ASA).
Purpose: To investigate the global cardiac volume, myocardial deformation, and hemodynamic characteristics before and during long-term follow-up after ASA in patients with HOCM.
Study type: Retrospective.
Subjects: Twenty-three patients (68.1 ± 8.6 years, 21.7% male) with HOCM who underwent MRI before and after ASA.
Field strength/sequence: A 3T, Two-dimensional fast imaging employing steady-state acquisition, inversion recovery-prepared fast gradient echo sequences, and cine and time-resolved three-dimensional cine phase-contrast (4D flow) MRI.
Assessment: Global left ventricular (LV) volume by cine, peak strain, and strain rate by myocardial feature-tracking MRI, and hemodynamic characteristics by 4D flow MRI.
Statistical tests: Paired t-test and Wilcoxon signed-rank test compared normally and nonnormally distributed data, respectively. Chi-squared or Fisher's exact tests were used to compare categorical data, as appropriate. Pearson's or Spearman's correlation coefficient evaluated the correlations. Statistical significance was set at q ≤ 0.10 or p < 0.05.
Results: In LV long-axis images, the global radial strain increased significantly (16.6% ± 5.8% vs. 20.1% ± 6.8%), whereas the global longitudinal strain decreased significantly after ASA (-10.5% ± 3.2% vs. -12.1% ± 3.5%). The diastolic LV anterior vortex area increased significantly after ASA (2256.1 [703.6, 4038.4] vs. 3826.1 [1914.3, 4820.1] mm2). Multiplication of the LV end-diastolic volume index, global circumferential strain, and diastolic radial peak strain rate in LV long-axis images revealed a significant correlation with the diastolic LV anterior vortex area (Rs = 0.43).
Data conclusions: Feature-tracking and 4D flow MRI revealed improved systolic and diastolic LV function during long-term follow-up after ASA. The diastolic LV vortex was associated with the combined parameters of LV volume and deformation. Comprehensive cardiac MRI may help understand the beneficial effects of ASA.
Evidence level: 3.
Technical efficacy: Stage 5.
Keywords: alcohol septal ablation; four‐dimensional flow magnetic resonance imaging; hypertrophic obstructive cardiomyopathy; strain; strain rate.
We studied patients with hypertrophic obstructive cardiomyopathy (HOCM), a heart disease that thickens the heart muscle and blocks blood flow. A treatment called alcohol septal ablation (ASA) can relieve this blockage, but its long‐term effects on heart function are not fully understood. Using advanced MRI techniques, we examined heart shape, pumping ability, and blood flow before and several years after ASA in 23 patients. We found that heart muscle motion and blood flow patterns improved after treatment, helping the heart pump and fill more efficiently. These findings show that MRI can reveal how ASA benefits patients over time.
© 2025 The Author(s). Journal of Magnetic Resonance Imaging published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.